hw/acpi/cpu.c

   1 #include "qemu/osdep.h"
   2 #include "hw/boards.h"
   3 #include "migration/vmstate.h"
   4 #include "hw/acpi/cpu.h"
   5 #include "qapi/error.h"
   6 #include "qapi/qapi-events-acpi.h"
   7 #include "trace.h"
   8 #include "sysemu/numa.h"
   9
  10 #define ACPI_CPU_HOTPLUG_REG_LEN 12
  11 #define ACPI_CPU_SELECTOR_OFFSET_WR 0
  12 #define ACPI_CPU_FLAGS_OFFSET_RW 4
  13 #define ACPI_CPU_CMD_OFFSET_WR 5
  14 #define ACPI_CPU_CMD_DATA_OFFSET_RW 8
  15 #define ACPI_CPU_CMD_DATA2_OFFSET_R 0
  16
  17 #define OVMF_CPUHP_SMI_CMD 4
  18
  19 enum {
  20     CPHP_GET_NEXT_CPU_WITH_EVENT_CMD = 0,
  21     CPHP_OST_EVENT_CMD = 1,
  22     CPHP_OST_STATUS_CMD = 2,
  23     CPHP_GET_CPU_ID_CMD = 3,
  24     CPHP_CMD_MAX
  25 };
  26
  27 static ACPIOSTInfo *acpi_cpu_device_status(int idx, AcpiCpuStatus *cdev)
  28 {
  29     ACPIOSTInfo *info = g_new0(ACPIOSTInfo, 1);
  30
  31     info->slot_type = ACPI_SLOT_TYPE_CPU;
  32     info->slot = g_strdup_printf("%d", idx);
  33     info->source = cdev->ost_event;
  34     info->status = cdev->ost_status;
  35     if (cdev->cpu) {
  36         DeviceState *dev = DEVICE(cdev->cpu);
  37         if (dev->id) {
  38             info->device = g_strdup(dev->id);
  39             info->has_device = true;
  40         }
  41     }
  42     return info;
  43 }
  44
  45 void acpi_cpu_ospm_status(CPUHotplugState *cpu_st, ACPIOSTInfoList ***list)
  46 {
  47     int i;
  48
  49     for (i = 0; i < cpu_st->dev_count; i++) {
  50         ACPIOSTInfoList *elem = g_new0(ACPIOSTInfoList, 1);
  51         elem->value = acpi_cpu_device_status(i, &cpu_st->devs[i]);
  52         elem->next = NULL;
  53         **list = elem;
  54         *list = &elem->next;
  55     }
  56 }
  57
  58 static uint64_t cpu_hotplug_rd(void *opaque, hwaddr addr, unsigned size)
  59 {
  60     uint64_t val = 0;
  61     CPUHotplugState *cpu_st = opaque;
  62     AcpiCpuStatus *cdev;
  63
  64     if (cpu_st->selector >= cpu_st->dev_count) {
  65         return val;
  66     }
  67
  68     cdev = &cpu_st->devs[cpu_st->selector];
  69     switch (addr) {
  70     case ACPI_CPU_FLAGS_OFFSET_RW: /* pack and return is_* fields */
  71         val |= cdev->cpu ? 1 : 0;
  72         val |= cdev->is_inserting ? 2 : 0;
  73         val |= cdev->is_removing  ? 4 : 0;
  74         trace_cpuhp_acpi_read_flags(cpu_st->selector, val);
  75         break;
  76     case ACPI_CPU_CMD_DATA_OFFSET_RW:
  77         switch (cpu_st->command) {
  78         case CPHP_GET_NEXT_CPU_WITH_EVENT_CMD:
  79            val = cpu_st->selector;
  80            break;
  81         case CPHP_GET_CPU_ID_CMD:
  82            val = cdev->arch_id & 0xFFFFFFFF;
  83            break;
  84         default:
  85            break;
  86         }
  87         trace_cpuhp_acpi_read_cmd_data(cpu_st->selector, val);
  88         break;
  89     case ACPI_CPU_CMD_DATA2_OFFSET_R:
  90         switch (cpu_st->command) {
  91         case CPHP_GET_NEXT_CPU_WITH_EVENT_CMD:
  92            val = 0;
  93            break;
  94         case CPHP_GET_CPU_ID_CMD:
  95            val = cdev->arch_id >> 32;
  96            break;
  97         default:
  98            break;
  99         }
 100         trace_cpuhp_acpi_read_cmd_data2(cpu_st->selector, val);
 101         break;
 102     default:
 103         break;
 104     }
 105     return val;
 106 }
 107
 108 static void cpu_hotplug_wr(void *opaque, hwaddr addr, uint64_t data,
 109                            unsigned int size)
 110 {
 111     CPUHotplugState *cpu_st = opaque;
 112     AcpiCpuStatus *cdev;
 113     ACPIOSTInfo *info;
 114
 115     assert(cpu_st->dev_count);
 116
 117     if (addr) {
 118         if (cpu_st->selector >= cpu_st->dev_count) {
 119             trace_cpuhp_acpi_invalid_idx_selected(cpu_st->selector);
 120             return;
 121         }
 122     }
 123
 124     switch (addr) {
 125     case ACPI_CPU_SELECTOR_OFFSET_WR: /* current CPU selector */
 126         cpu_st->selector = data;
 127         trace_cpuhp_acpi_write_idx(cpu_st->selector);
 128         break;
 129     case ACPI_CPU_FLAGS_OFFSET_RW: /* set is_* fields  */
 130         cdev = &cpu_st->devs[cpu_st->selector];
 131         if (data & 2) { /* clear insert event */
 132             cdev->is_inserting = false;
 133             trace_cpuhp_acpi_clear_inserting_evt(cpu_st->selector);
 134         } else if (data & 4) { /* clear remove event */
 135             cdev->is_removing = false;
 136             trace_cpuhp_acpi_clear_remove_evt(cpu_st->selector);
 137         } else if (data & 8) {
 138             DeviceState *dev = NULL;
 139             HotplugHandler *hotplug_ctrl = NULL;
 140
 141             if (!cdev->cpu || cdev->cpu == first_cpu) {
 142                 trace_cpuhp_acpi_ejecting_invalid_cpu(cpu_st->selector);
 143                 break;
 144             }
 145
 146             trace_cpuhp_acpi_ejecting_cpu(cpu_st->selector);
 147             dev = DEVICE(cdev->cpu);
 148             hotplug_ctrl = qdev_get_hotplug_handler(dev);
 149             hotplug_handler_unplug(hotplug_ctrl, dev, NULL);
 150             object_unparent(OBJECT(dev));
 151         }
 152         break;
 153     case ACPI_CPU_CMD_OFFSET_WR:
 154         trace_cpuhp_acpi_write_cmd(cpu_st->selector, data);
 155         if (data < CPHP_CMD_MAX) {
 156             cpu_st->command = data;
 157             if (cpu_st->command == CPHP_GET_NEXT_CPU_WITH_EVENT_CMD) {
 158                 uint32_t iter = cpu_st->selector;
 159
 160                 do {
 161                     cdev = &cpu_st->devs[iter];
 162                     if (cdev->is_inserting || cdev->is_removing) {
 163                         cpu_st->selector = iter;
 164                         trace_cpuhp_acpi_cpu_has_events(cpu_st->selector,
 165                             cdev->is_inserting, cdev->is_removing);
 166                         break;
 167                     }
 168                     iter = iter + 1 < cpu_st->dev_count ? iter + 1 : 0;
 169                 } while (iter != cpu_st->selector);
 170             }
 171         }
 172         break;
 173     case ACPI_CPU_CMD_DATA_OFFSET_RW:
 174         switch (cpu_st->command) {
 175         case CPHP_OST_EVENT_CMD: {
 176            cdev = &cpu_st->devs[cpu_st->selector];
 177            cdev->ost_event = data;
 178            trace_cpuhp_acpi_write_ost_ev(cpu_st->selector, cdev->ost_event);
 179            break;
 180         }
 181         case CPHP_OST_STATUS_CMD: {
 182            cdev = &cpu_st->devs[cpu_st->selector];
 183            cdev->ost_status = data;
 184            info = acpi_cpu_device_status(cpu_st->selector, cdev);
 185            qapi_event_send_acpi_device_ost(info);
 186            qapi_free_ACPIOSTInfo(info);
 187            trace_cpuhp_acpi_write_ost_status(cpu_st->selector,
 188                                              cdev->ost_status);
 189            break;
 190         }
 191         default:
 192            break;
 193         }
 194         break;
 195     default:
 196         break;
 197     }
 198 }
 199
 200 static const MemoryRegionOps cpu_hotplug_ops = {
 201     .read = cpu_hotplug_rd,
 202     .write = cpu_hotplug_wr,
 203     .endianness = DEVICE_LITTLE_ENDIAN,
 204     .valid = {
 205         .min_access_size = 1,
 206         .max_access_size = 4,
 207     },
 208 };
 209
 210 void cpu_hotplug_hw_init(MemoryRegion *as, Object *owner,
 211                          CPUHotplugState *state, hwaddr base_addr)
 212 {
 213     MachineState *machine = MACHINE(qdev_get_machine());
 214     MachineClass *mc = MACHINE_GET_CLASS(machine);
 215     const CPUArchIdList *id_list;
 216     int i;
 217
 218     assert(mc->possible_cpu_arch_ids);
 219     id_list = mc->possible_cpu_arch_ids(machine);
 220     state->dev_count = id_list->len;
 221     state->devs = g_new0(typeof(*state->devs), state->dev_count);
 222     for (i = 0; i < id_list->len; i++) {
 223         state->devs[i].cpu =  CPU(id_list->cpus[i].cpu);
 224         state->devs[i].arch_id = id_list->cpus[i].arch_id;
 225     }
 226     memory_region_init_io(&state->ctrl_reg, owner, &cpu_hotplug_ops, state,
 227                           "acpi-cpu-hotplug", ACPI_CPU_HOTPLUG_REG_LEN);
 228     memory_region_add_subregion(as, base_addr, &state->ctrl_reg);
 229 }
 230
 231 static AcpiCpuStatus *get_cpu_status(CPUHotplugState *cpu_st, DeviceState *dev)
 232 {
 233     CPUClass *k = CPU_GET_CLASS(dev);
 234     uint64_t cpu_arch_id = k->get_arch_id(CPU(dev));
 235     int i;
 236
 237     for (i = 0; i < cpu_st->dev_count; i++) {
 238         if (cpu_arch_id == cpu_st->devs[i].arch_id) {
 239             return &cpu_st->devs[i];
 240         }
 241     }
 242     return NULL;
 243 }
 244
 245 void acpi_cpu_plug_cb(HotplugHandler *hotplug_dev,
 246                       CPUHotplugState *cpu_st, DeviceState *dev, Error **errp)
 247 {
 248     AcpiCpuStatus *cdev;
 249
 250     cdev = get_cpu_status(cpu_st, dev);
 251     if (!cdev) {
 252         return;
 253     }
 254
 255     cdev->cpu = CPU(dev);
 256     if (dev->hotplugged) {
 257         cdev->is_inserting = true;
 258         acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS);
 259     }
 260 }
 261
 262 void acpi_cpu_unplug_request_cb(HotplugHandler *hotplug_dev,
 263                                 CPUHotplugState *cpu_st,
 264                                 DeviceState *dev, Error **errp)
 265 {
 266     AcpiCpuStatus *cdev;
 267
 268     cdev = get_cpu_status(cpu_st, dev);
 269     if (!cdev) {
 270         return;
 271     }
 272
 273     cdev->is_removing = true;
 274     acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS);
 275 }
 276
 277 void acpi_cpu_unplug_cb(CPUHotplugState *cpu_st,
 278                         DeviceState *dev, Error **errp)
 279 {
 280     AcpiCpuStatus *cdev;
 281
 282     cdev = get_cpu_status(cpu_st, dev);
 283     if (!cdev) {
 284         return;
 285     }
 286
 287     cdev->cpu = NULL;
 288 }
 289
 290 static const VMStateDescription vmstate_cpuhp_sts = {
 291     .name = "CPU hotplug device state",
 292     .version_id = 1,
 293     .minimum_version_id = 1,
 294     .minimum_version_id_old = 1,
 295     .fields      = (VMStateField[]) {
 296         VMSTATE_BOOL(is_inserting, AcpiCpuStatus),
 297         VMSTATE_BOOL(is_removing, AcpiCpuStatus),
 298         VMSTATE_UINT32(ost_event, AcpiCpuStatus),
 299         VMSTATE_UINT32(ost_status, AcpiCpuStatus),
 300         VMSTATE_END_OF_LIST()
 301     }
 302 };
 303
 304 const VMStateDescription vmstate_cpu_hotplug = {
 305     .name = "CPU hotplug state",
 306     .version_id = 1,
 307     .minimum_version_id = 1,
 308     .minimum_version_id_old = 1,
 309     .fields      = (VMStateField[]) {
 310         VMSTATE_UINT32(selector, CPUHotplugState),
 311         VMSTATE_UINT8(command, CPUHotplugState),
 312         VMSTATE_STRUCT_VARRAY_POINTER_UINT32(devs, CPUHotplugState, dev_count,
 313                                              vmstate_cpuhp_sts, AcpiCpuStatus),
 314         VMSTATE_END_OF_LIST()
 315     }
 316 };
 317
 318 #define CPU_NAME_FMT      "C%.03X"
 319 #define CPUHP_RES_DEVICE  "PRES"
 320 #define CPU_LOCK          "CPLK"
 321 #define CPU_STS_METHOD    "CSTA"
 322 #define CPU_SCAN_METHOD   "CSCN"
 323 #define CPU_NOTIFY_METHOD "CTFY"
 324 #define CPU_EJECT_METHOD  "CEJ0"
 325 #define CPU_OST_METHOD    "COST"
 326 #define CPU_ADDED_LIST    "CNEW"
 327
 328 #define CPU_ENABLED       "CPEN"
 329 #define CPU_SELECTOR      "CSEL"
 330 #define CPU_COMMAND       "CCMD"
 331 #define CPU_DATA          "CDAT"
 332 #define CPU_INSERT_EVENT  "CINS"
 333 #define CPU_REMOVE_EVENT  "CRMV"
 334 #define CPU_EJECT_EVENT   "CEJ0"
 335
 336 void build_cpus_aml(Aml *table, MachineState *machine, CPUHotplugFeatures opts,
 337                     hwaddr io_base,
 338                     const char *res_root,
 339                     const char *event_handler_method)
 340 {
 341     Aml *ifctx;
 342     Aml *field;
 343     Aml *method;
 344     Aml *cpu_ctrl_dev;
 345     Aml *cpus_dev;
 346     Aml *zero = aml_int(0);
 347     Aml *one = aml_int(1);
 348     Aml *sb_scope = aml_scope("_SB");
 349     MachineClass *mc = MACHINE_GET_CLASS(machine);
 350     const CPUArchIdList *arch_ids = mc->possible_cpu_arch_ids(machine);
 351     char *cphp_res_path = g_strdup_printf("%s." CPUHP_RES_DEVICE, res_root);
 352     Object *obj = object_resolve_path_type("", TYPE_ACPI_DEVICE_IF, NULL);
 353     AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_GET_CLASS(obj);
 354     AcpiDeviceIf *adev = ACPI_DEVICE_IF(obj);
 355
 356     cpu_ctrl_dev = aml_device("%s", cphp_res_path);
 357     {
 358         Aml *crs;
 359
 360         aml_append(cpu_ctrl_dev,
 361             aml_name_decl("_HID", aml_eisaid("PNP0A06")));
 362         aml_append(cpu_ctrl_dev,
 363             aml_name_decl("_UID", aml_string("CPU Hotplug resources")));
 364         aml_append(cpu_ctrl_dev, aml_mutex(CPU_LOCK, 0));
 365
 366         crs = aml_resource_template();
 367         aml_append(crs, aml_io(AML_DECODE16, io_base, io_base, 1,
 368                                ACPI_CPU_HOTPLUG_REG_LEN));
 369         aml_append(cpu_ctrl_dev, aml_name_decl("_CRS", crs));
 370
 371         /* declare CPU hotplug MMIO region with related access fields */
 372         aml_append(cpu_ctrl_dev,
 373             aml_operation_region("PRST", AML_SYSTEM_IO, aml_int(io_base),
 374                                  ACPI_CPU_HOTPLUG_REG_LEN));
 375
 376         field = aml_field("PRST", AML_BYTE_ACC, AML_NOLOCK,
 377                           AML_WRITE_AS_ZEROS);
 378         aml_append(field, aml_reserved_field(ACPI_CPU_FLAGS_OFFSET_RW * 8));
 379         /* 1 if enabled, read only */
 380         aml_append(field, aml_named_field(CPU_ENABLED, 1));
 381         /* (read) 1 if has a insert event. (write) 1 to clear event */
 382         aml_append(field, aml_named_field(CPU_INSERT_EVENT, 1));
 383         /* (read) 1 if has a remove event. (write) 1 to clear event */
 384         aml_append(field, aml_named_field(CPU_REMOVE_EVENT, 1));
 385         /* initiates device eject, write only */
 386         aml_append(field, aml_named_field(CPU_EJECT_EVENT, 1));
 387         aml_append(field, aml_reserved_field(4));
 388         aml_append(field, aml_named_field(CPU_COMMAND, 8));
 389         aml_append(cpu_ctrl_dev, field);
 390
 391         field = aml_field("PRST", AML_DWORD_ACC, AML_NOLOCK, AML_PRESERVE);
 392         /* CPU selector, write only */
 393         aml_append(field, aml_named_field(CPU_SELECTOR, 32));
 394         /* flags + cmd + 2byte align */
 395         aml_append(field, aml_reserved_field(4 * 8));
 396         aml_append(field, aml_named_field(CPU_DATA, 32));
 397         aml_append(cpu_ctrl_dev, field);
 398
 399         if (opts.has_legacy_cphp) {
 400             method = aml_method("_INI", 0, AML_SERIALIZED);
 401             /* switch off legacy CPU hotplug HW and use new one,
 402              * on reboot system is in new mode and writing 0
 403              * in CPU_SELECTOR selects BSP, which is NOP at
 404              * the time _INI is called */
 405             aml_append(method, aml_store(zero, aml_name(CPU_SELECTOR)));
 406             aml_append(cpu_ctrl_dev, method);
 407         }
 408     }
 409     aml_append(sb_scope, cpu_ctrl_dev);
 410
 411     cpus_dev = aml_device("\\_SB.CPUS");
 412     {
 413         int i;
 414         Aml *ctrl_lock = aml_name("%s.%s", cphp_res_path, CPU_LOCK);
 415         Aml *cpu_selector = aml_name("%s.%s", cphp_res_path, CPU_SELECTOR);
 416         Aml *is_enabled = aml_name("%s.%s", cphp_res_path, CPU_ENABLED);
 417         Aml *cpu_cmd = aml_name("%s.%s", cphp_res_path, CPU_COMMAND);
 418         Aml *cpu_data = aml_name("%s.%s", cphp_res_path, CPU_DATA);
 419         Aml *ins_evt = aml_name("%s.%s", cphp_res_path, CPU_INSERT_EVENT);
 420         Aml *rm_evt = aml_name("%s.%s", cphp_res_path, CPU_REMOVE_EVENT);
 421         Aml *ej_evt = aml_name("%s.%s", cphp_res_path, CPU_EJECT_EVENT);
 422
 423         aml_append(cpus_dev, aml_name_decl("_HID", aml_string("ACPI0010")));
 424         aml_append(cpus_dev, aml_name_decl("_CID", aml_eisaid("PNP0A05")));
 425
 426         method = aml_method(CPU_NOTIFY_METHOD, 2, AML_NOTSERIALIZED);
 427         for (i = 0; i < arch_ids->len; i++) {
 428             Aml *cpu = aml_name(CPU_NAME_FMT, i);
 429             Aml *uid = aml_arg(0);
 430             Aml *event = aml_arg(1);
 431
 432             ifctx = aml_if(aml_equal(uid, aml_int(i)));
 433             {
 434                 aml_append(ifctx, aml_notify(cpu, event));
 435             }
 436             aml_append(method, ifctx);
 437         }
 438         aml_append(cpus_dev, method);
 439
 440         method = aml_method(CPU_STS_METHOD, 1, AML_SERIALIZED);
 441         {
 442             Aml *idx = aml_arg(0);
 443             Aml *sta = aml_local(0);
 444
 445             aml_append(method, aml_acquire(ctrl_lock, 0xFFFF));
 446             aml_append(method, aml_store(idx, cpu_selector));
 447             aml_append(method, aml_store(zero, sta));
 448             ifctx = aml_if(aml_equal(is_enabled, one));
 449             {
 450                 aml_append(ifctx, aml_store(aml_int(0xF), sta));
 451             }
 452             aml_append(method, ifctx);
 453             aml_append(method, aml_release(ctrl_lock));
 454             aml_append(method, aml_return(sta));
 455         }
 456         aml_append(cpus_dev, method);
 457
 458         method = aml_method(CPU_EJECT_METHOD, 1, AML_SERIALIZED);
 459         {
 460             Aml *idx = aml_arg(0);
 461
 462             aml_append(method, aml_acquire(ctrl_lock, 0xFFFF));
 463             aml_append(method, aml_store(idx, cpu_selector));
 464             aml_append(method, aml_store(one, ej_evt));
 465             aml_append(method, aml_release(ctrl_lock));
 466         }
 467         aml_append(cpus_dev, method);
 468
 469         method = aml_method(CPU_SCAN_METHOD, 0, AML_SERIALIZED);
 470         {
 471             const uint8_t max_cpus_per_pass = 255;
 472             Aml *else_ctx;
 473             Aml *while_ctx, *while_ctx2;
 474             Aml *has_event = aml_local(0);
 475             Aml *dev_chk = aml_int(1);
 476             Aml *eject_req = aml_int(3);
 477             Aml *next_cpu_cmd = aml_int(CPHP_GET_NEXT_CPU_WITH_EVENT_CMD);
 478             Aml *num_added_cpus = aml_local(1);
 479             Aml *cpu_idx = aml_local(2);
 480             Aml *uid = aml_local(3);
 481             Aml *has_job = aml_local(4);
 482             Aml *new_cpus = aml_name(CPU_ADDED_LIST);
 483
 484             aml_append(method, aml_acquire(ctrl_lock, 0xFFFF));
 485
 486             /*
 487              * Windows versions newer than XP (including Windows 10/Windows
 488              * Server 2019), do support* VarPackageOp but, it is cripled to hold
 489              * the same elements number as old PackageOp.
 490              * For compatibility with Windows XP (so it won't crash) use ACPI1.0
 491              * PackageOp which can hold max 255 elements.
 492              *
 493              * use named package as old Windows don't support it in local var
 494              */
 495             aml_append(method, aml_name_decl(CPU_ADDED_LIST,
 496                                              aml_package(max_cpus_per_pass)));
 497
 498             aml_append(method, aml_store(zero, uid));
 499             aml_append(method, aml_store(one, has_job));
 500             /*
 501              * CPU_ADDED_LIST can hold limited number of elements, outer loop
 502              * allows to process CPUs in batches which let us to handle more
 503              * CPUs than CPU_ADDED_LIST can hold.
 504              */
 505             while_ctx2 = aml_while(aml_equal(has_job, one));
 506             {
 507                 aml_append(while_ctx2, aml_store(zero, has_job));
 508
 509                 aml_append(while_ctx2, aml_store(one, has_event));
 510                 aml_append(while_ctx2, aml_store(zero, num_added_cpus));
 511
 512                 /*
 513                  * Scan CPUs, till there are CPUs with events or
 514                  * CPU_ADDED_LIST capacity is exhausted
 515                  */
 516                 while_ctx = aml_while(aml_land(aml_equal(has_event, one),
 517                                       aml_lless(uid, aml_int(arch_ids->len))));
 518                 {
 519                      /*
 520                       * clear loop exit condition, ins_evt/rm_evt checks will
 521                       * set it to 1 while next_cpu_cmd returns a CPU with events
 522                       */
 523                      aml_append(while_ctx, aml_store(zero, has_event));
 524
 525                      aml_append(while_ctx, aml_store(uid, cpu_selector));
 526                      aml_append(while_ctx, aml_store(next_cpu_cmd, cpu_cmd));
 527
 528                      /*
 529                       * wrap around case, scan is complete, exit loop.
 530                       * It happens since events are not cleared in scan loop,
 531                       * so next_cpu_cmd continues to find already processed CPUs
 532                       */
 533                      ifctx = aml_if(aml_lless(cpu_data, uid));
 534                      {
 535                          aml_append(ifctx, aml_break());
 536                      }
 537                      aml_append(while_ctx, ifctx);
 538
 539                      /*
 540                       * if CPU_ADDED_LIST is full, exit inner loop and process
 541                       * collected CPUs
 542                       */
 543                      ifctx = aml_if(
 544                          aml_equal(num_added_cpus, aml_int(max_cpus_per_pass)));
 545                      {
 546                          aml_append(ifctx, aml_store(one, has_job));
 547                          aml_append(ifctx, aml_break());
 548                      }
 549                      aml_append(while_ctx, ifctx);
 550
 551                      aml_append(while_ctx, aml_store(cpu_data, uid));
 552                      ifctx = aml_if(aml_equal(ins_evt, one));
 553                      {
 554                          /* cache added CPUs to Notify/Wakeup later */
 555                          aml_append(ifctx, aml_store(uid,
 556                              aml_index(new_cpus, num_added_cpus)));
 557                          aml_append(ifctx, aml_increment(num_added_cpus));
 558                          aml_append(ifctx, aml_store(one, has_event));
 559                      }
 560                      aml_append(while_ctx, ifctx);
 561                      else_ctx = aml_else();
 562                      ifctx = aml_if(aml_equal(rm_evt, one));
 563                      {
 564                          aml_append(ifctx,
 565                              aml_call2(CPU_NOTIFY_METHOD, uid, eject_req));
 566                          aml_append(ifctx, aml_store(one, rm_evt));
 567                          aml_append(ifctx, aml_store(one, has_event));
 568                      }
 569                      aml_append(else_ctx, ifctx);
 570                      aml_append(while_ctx, else_ctx);
 571                      aml_append(while_ctx, aml_increment(uid));
 572                 }
 573                 aml_append(while_ctx2, while_ctx);
 574
 575                 /*
 576                  * in case FW negotiated ICH9_LPC_SMI_F_CPU_HOTPLUG_BIT,
 577                  * make upcall to FW, so it can pull in new CPUs before
 578                  * OS is notified and wakes them up
 579                  */
 580                 if (opts.smi_path) {
 581                     ifctx = aml_if(aml_lgreater(num_added_cpus, zero));
 582                     {
 583                         aml_append(ifctx, aml_store(aml_int(OVMF_CPUHP_SMI_CMD),
 584                             aml_name("%s", opts.smi_path)));
 585                     }
 586                     aml_append(while_ctx2, ifctx);
 587                 }
 588
 589                 /* Notify OSPM about new CPUs and clear insert events */
 590                 aml_append(while_ctx2, aml_store(zero, cpu_idx));
 591                 while_ctx = aml_while(aml_lless(cpu_idx, num_added_cpus));
 592                 {
 593                     aml_append(while_ctx,
 594                         aml_store(aml_derefof(aml_index(new_cpus, cpu_idx)),
 595                                   uid));
 596                     aml_append(while_ctx,
 597                         aml_call2(CPU_NOTIFY_METHOD, uid, dev_chk));
 598                     aml_append(while_ctx, aml_store(uid, aml_debug()));
 599                     aml_append(while_ctx, aml_store(uid, cpu_selector));
 600                     aml_append(while_ctx, aml_store(one, ins_evt));
 601                     aml_append(while_ctx, aml_increment(cpu_idx));
 602                 }
 603                 aml_append(while_ctx2, while_ctx);
 604                 /*
 605                  * If another batch is needed, then it will resume scanning
 606                  * exactly at -- and not after -- the last CPU that's currently
 607                  * in CPU_ADDED_LIST. In other words, the last CPU in
 608                  * CPU_ADDED_LIST is going to be re-checked. That's OK: we've
 609                  * just cleared the insert event for *all* CPUs in
 610                  * CPU_ADDED_LIST, including the last one. So the scan will
 611                  * simply seek past it.
 612                  */
 613             }
 614             aml_append(method, while_ctx2);
 615             aml_append(method, aml_release(ctrl_lock));
 616         }
 617         aml_append(cpus_dev, method);
 618
 619         method = aml_method(CPU_OST_METHOD, 4, AML_SERIALIZED);
 620         {
 621             Aml *uid = aml_arg(0);
 622             Aml *ev_cmd = aml_int(CPHP_OST_EVENT_CMD);
 623             Aml *st_cmd = aml_int(CPHP_OST_STATUS_CMD);
 624
 625             aml_append(method, aml_acquire(ctrl_lock, 0xFFFF));
 626             aml_append(method, aml_store(uid, cpu_selector));
 627             aml_append(method, aml_store(ev_cmd, cpu_cmd));
 628             aml_append(method, aml_store(aml_arg(1), cpu_data));
 629             aml_append(method, aml_store(st_cmd, cpu_cmd));
 630             aml_append(method, aml_store(aml_arg(2), cpu_data));
 631             aml_append(method, aml_release(ctrl_lock));
 632         }
 633         aml_append(cpus_dev, method);
 634
 635         /* build Processor object for each processor */
 636         for (i = 0; i < arch_ids->len; i++) {
 637             Aml *dev;
 638             Aml *uid = aml_int(i);
 639             GArray *madt_buf = g_array_new(0, 1, 1);
 640             int arch_id = arch_ids->cpus[i].arch_id;
 641
 642             if (opts.acpi_1_compatible && arch_id < 255) {
 643                 dev = aml_processor(i, 0, 0, CPU_NAME_FMT, i);
 644             } else {
 645                 dev = aml_device(CPU_NAME_FMT, i);
 646                 aml_append(dev, aml_name_decl("_HID", aml_string("ACPI0007")));
 647                 aml_append(dev, aml_name_decl("_UID", uid));
 648             }
 649
 650             method = aml_method("_STA", 0, AML_SERIALIZED);
 651             aml_append(method, aml_return(aml_call1(CPU_STS_METHOD, uid)));
 652             aml_append(dev, method);
 653
 654             /* build _MAT object */
 655             assert(adevc && adevc->madt_cpu);
 656             adevc->madt_cpu(adev, i, arch_ids, madt_buf);
 657             switch (madt_buf->data[0]) {
 658             case ACPI_APIC_PROCESSOR: {
 659                 AcpiMadtProcessorApic *apic = (void *)madt_buf->data;
 660                 apic->flags = cpu_to_le32(1);
 661                 break;
 662             }
 663             case ACPI_APIC_LOCAL_X2APIC: {
 664                 AcpiMadtProcessorX2Apic *apic = (void *)madt_buf->data;
 665                 apic->flags = cpu_to_le32(1);
 666                 break;
 667             }
 668             default:
 669                 assert(0);
 670             }
 671             aml_append(dev, aml_name_decl("_MAT",
 672                 aml_buffer(madt_buf->len, (uint8_t *)madt_buf->data)));
 673             g_array_free(madt_buf, true);
 674
 675             if (CPU(arch_ids->cpus[i].cpu) != first_cpu) {
 676                 method = aml_method("_EJ0", 1, AML_NOTSERIALIZED);
 677                 aml_append(method, aml_call1(CPU_EJECT_METHOD, uid));
 678                 aml_append(dev, method);
 679             }
 680
 681             method = aml_method("_OST", 3, AML_SERIALIZED);
 682             aml_append(method,
 683                 aml_call4(CPU_OST_METHOD, uid, aml_arg(0),
 684                           aml_arg(1), aml_arg(2))
 685             );
 686             aml_append(dev, method);
 687
 688             /* Linux guests discard SRAT info for non-present CPUs
 689              * as a result _PXM is required for all CPUs which might
 690              * be hot-plugged. For simplicity, add it for all CPUs.
 691              */
 692             if (arch_ids->cpus[i].props.has_node_id) {
 693                 aml_append(dev, aml_name_decl("_PXM",
 694                            aml_int(arch_ids->cpus[i].props.node_id)));
 695             }
 696
 697             aml_append(cpus_dev, dev);
 698         }
 699     }
 700     aml_append(sb_scope, cpus_dev);
 701     aml_append(table, sb_scope);
 702
 703     method = aml_method(event_handler_method, 0, AML_NOTSERIALIZED);
 704     aml_append(method, aml_call0("\\_SB.CPUS." CPU_SCAN_METHOD));
 705     aml_append(table, method);
 706
 707     g_free(cphp_res_path);
 708 }